.top {
    position: fixed;
    cursor: pointer;
    z-index: 901;
    bottom: 20px;
    right: 10px;
    width: 34px;
    height: 34px;
    line-height: 34px;
    text-align: center;
    transform: translate(90deg);
    color: #888;
    transform: rotate(-90deg);
    display: inline-block;
    span {
        background: #888;
    }
}